Variable orifice gas burner



May 11, 1954 H. M. GODSEY VARIABLE ORIFICE GAS BURNER Original Filed Jan. '8, 1948 35 INVENTOR. ff z zkkell Eadie main 151$ Patented May 11, 1954 UNITED STATES PATENT OFFICE Continuation of application Serial No. 1,243, January 8, 1948. This application October 7, 1949,

Serial No. 120,131

Claims. (Cl. 158117) This invention relates to gas burners which are adapted for burning different kinds of gas selectively. An object of the invention is to provide an apparatus which is provided with a burning part which is readily adapted for alteration in size for use with gases of difierent calorific value, for example, natural gas or butane.

A further object of the invention is to provide a gas burner which is adapted for selectively burning diiferent gases but which produces a flame of similar shape regardless of wihch gas and corresponding adjustment is used. The gas burner, according to the invention, can be of identical construction for burning any one of a plurality of gases, the only alteration required being a small difierence in the relative position of some of the parts in assembling the burner parts.

In the accompanying drawings several embodiments of the invention are illustrated by way of example.

In the drawings,

Fig. l is an elevation partly in section of one embodiment of the invention with the burner tube and cap arranged in one relative position of adjustment to form a narrow burning slot or slots for burning a relatively rich gas.

Fig. 2 is a View similar to Fig. 1, with the lower part omitted, showing the burner tube and cap in different relative positions to form a wider slot or slots for burning a gas of relatively lower calorific value.

Fig. 3 is a sectional view on line III-III of Fig. 1.

Fig. 4 is a perspective view of the burner tube of Fig. 1, with the cap removed.

Fig. 5 is a side view, partly in section, of the upper part of a gas burner according to a second embodiment of the invention.

Fig. 6 is a perspective view of the upper part of the burner tube of the embodiment of Fig. 5 with the cap removed.

Fig. '7 is a sectional View on the line VII-VII of Fig. 5.

Fig. 8 is a. sectional view of the burner cap on the line VIII--VIII of Fig. 7 with the supporting posts omitted.

Fig. 9 is a sectional view on the line IX-IX of Fig. '7 with the supporting posts omitted.

Fig. 10 is a side view of a cap having a different peripheral shape for producing a conical flame.

The gas burner according to the invention as embodied in Figs. 1-4 inclusive comprises a vertically arranged tube I having an inlet 2 for gas at its lower end; one or more inlets 4 in its side wall for primary air. Extending upwardly from the gas inlet and air inlet is a mixing tube portion 5 which may be somewhat Venturi-shaped, as indicated in dotted lines, in order to produce the reduced pressure at the air inlet for drawing in the primary air. It will be understood that the features above described are substantially conventional in gas burners and have been described herein in order to disclose a fully operative apparatus.

At its upper end portion the burner tube l is provided with four upwardly extending posts 6, i, '8, 9 which are connected together in pairs by partially circular bridges l0 and Il. On top of these posts and bridges is arranged a cap l2 which is preferably a flat circular disc having substantial thickness, which in the embodiment of Figs. 1-4. is of somewhat greater diameter than the tube upon which it is supported. The cap is provided with an annular recess M in its bottom surface, the depth of the recess at two opposite portions l5, It being greater than the other two opposite portions l1, [8. The length of the two deeper portions [5, I6 is at least as long as the distance between the opposite edges of the pairs of posts between which the bridges extend, and the location of the said deeper portions corresponds to the positions of the bridges, so that when the cap I2 is placed on the upper end of the tube with the deeper portions of the recess in registry with bridges, the bridges and supporting posts will enter the deeper recess portions and the cap will be supported at a relatively low level. The burner ports 20 defined between the upper edge of the tube, the lower edge of cap I2 and the respective posts will be of small vertical dimension and thus thin flat burner ports are provided and a thin flat flame is produced in operation. Such an adjustment would be preferable when burning a gas of especially high calorific value such as butane.

In Fig. l the cap is arranged on the tube in such manner as to provide the thin burner ports, whereas in Fig. 2 the cap is so turned that the shallower portions l'i', l8 of the groove register with the posts and bridges l0, II and the cap is therefore supported at a higher level with its lower surface at a greater distance from the upper edge of the tube so that thicker burner ports are provided suitable for a gas of comparatively low calorific value such as natural gas.

In Figs. 5 to 9 of the drawing a second embodiment of the invention is shown. The lower part of the burner tube 25 may be similar to that of the first embodiment whereas the difference resides in the formation of the means for supporting burner cap and in the cap itself. The upper part of the burner tube is provided with a plurality of posts 26, 21, 28, and 29, four in number being shown. However, only three posts or more than four may be provided if desired. The cap in this embodiment is provided with an annular recess 30 in its lower surface, and at locations corresponding to the positions of the posts is provided with deeperrecesses. The cap may be placed on the burner tube with the posts extending into the deeper recesses as shown in Fig. 5 to form. burner ports of smaller vertical dimension for burning gas of high calorific value, or with the bottoms of the shallower parts of the recess engaging with and supported by the upper ends of the posts. In this latter case the burner ports are thicker in the vertical dimension and adapted to burn gas of lower calorific value.

Since the burner ports are directed substantially horizontally outwardly and the upper edges thereof, constituted by the lower surface of the cap outwardly of the annular recess, extend outwardly beyond the tube, the burner produces an exceptionally flat circular flame. When the burners are used in gangs in furnaces in proximity to each other asubstantia-lly continuous sheet of flame can be produced across a fire box of a furnace thus providing for better entrapment of secondary air with improved combustion results.

Fig. 10 is aside view ofamodified form of a cap 35. The cap is provided with an annular groove (not visible) in its bottom surface of different depth at di ifercnt portions similarly as in either of the first twoembodiments and for the same purpose. The outer surface of the cap is tapering downwardly, asindicated: at 35,

'andat its lower edge is ofapproximately the same diameteras aburner tube. A cap of this shape produces a conical flame spreading upwardly instead of a flat flame.

This application is a continuation of my application Serial No. l,243,-entitled Variable Orifice Gas Burners, filed January 8, 1948, now forfeited.

I claim:

1. In a gas burner atube having .longitudinally extending posts at one end, a cap supported by said posts said cap having recesses formed in its face toward the tube, some of said recesses being of the same depth and others being of different depths, recesses of the same depth being located in positions corresponding to the positions of said posts whereby said posts can extend into sets of recesses" of different depths and support thecap at different-distances from the end of the tube according to which set of recesses is employed and whereby the end of the tube and the cap define edges of burner ports of different dimensions.

2. A gas burner according to claim 1 and in which the recesses are connected so as to form a continuous annular groove, parts of which are of greater depth than other parts.

3. A gas burner according to claim 2 and in which some of the posts are joined at their outer ends by ring segments to form partly annular bridges and the annular extent of the deeper portions of the annular groove is at least as great as that of the bridges and their supporting. posts so as to be able toreceive said bridges: and

posts.

4. A gas burner according to claim 1 and in which the cap has a flat lower face of greater diameter than the burner tube so as to extend outwardly beyond the tube and direct the flame issuing from the burner ports into a flat sheet.

5. A gas burner according to claim 1 and in which the cap has a lower face of about the same diameter as the burner tube and anouter surface flaring upwardly to direct a flame issuing from the burner ports into an inverted cone shape.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 485,910 Dean .Nov. 8, 1892 738,290 Burr Sept. 8, 1903 1,815,322 Meader' July 21, 1931 2,185,886 Caldwell Jan. 2, 1940 FOREIGN PA'IENTS Number Country Date 167,668 Germany; Feb. 6,1906 1,689 Netherlands Oct. 3, 1916 

